The Midnight Beast10pm, E4

There's friction in the band this week. Ash is warned that his randy gland is among the issues causing the fissure, as is Dru's distinct lacking in the same department. A romantic intervention in the caff seems to have a temporary effect, until Dru's new love interest proves less a steadying influence than an obsessive loon. With a hit rate of about one in 20 gags, the sitcom from these YouTube sensations is considerably less likely to grab the 40-odd million views it has had online. Ben Arnold

Natural World: Tiger Island8pm, BBC2

The habitat of the Sumatran tiger has been destroyed by the island's deforestation, turning the majestic creatures, among the last island tigers on the planet, into maneaters. As such they are hunted and killed, or kept captive in desperate conditions. Whether they can be rehabilitated and released back into the wild is unknown territory. But maverick millionaire Tomy Winata is doing just that, releasing the tigers on to his own land with little regard for the village nearby. Is this reckless? Or could it save the species from extinction? BA

BBC Proms 20127.30pm, BBC4

Conductor Daniel Barenboim leads the West-Eastern Divan Orchestra in its Royal Albert Hall romp through Beethoven's symphonies: tonight it's the fifth and sixth. The West-Eastern Divan Orchestra is the altogether admirable ensemble founded in 1999 by the Argentinian-Israeli conductor Barenboim in association with the late Palestinian academic Edward Said and includes musicians from all over the Middle East. Andrew Mueller

The Churchills8pm, Channel 4

One of the Churchills in question is Winston. The other, less well-known today, is his ancestor John Churchill, 1st Duke of Marlborough. The Duke's claim to fame was defeating France in the Nine Years' War in the early-18th century. Winston wrote a mammoth biography of Marlborough, which, for historian David Starkey, is crucial to our understanding of the future wartime prime minister, being "a book about history that changed history". Starkey gallops through his thesis with an unconcealed gushing admiration for his subjects. Martin Skegg

Obsessive Compulsive Hoarder: The Big Clear Out9pm, Channel 4

Hoarder Richard Wallace was the subject of a Channel 4 documentary, as his collection of clutter threatened to take over his house. The follow-up looks at how he's doing six months later. Despite Andy the landscape gardener rounding up villagers to help with a clearout, there's still an alarming amount of mess. The extent of Richard's hoarding is revealed with the discovery of a "death tunnel" that he has to crawl through in his kitchen, prompting Andy to bring in a mental health team for support. Hannah Verdier

Frontline: The New Asylums9pm, PBS

In 2005, when this harrowing documentary was made, fewer than 55,000 mentally ill Americans were being treated in psychiatric hospitals – almost 10 times that number are in jail. Frontline visits Ohio State Penitentiary and sits in on mental health meetings and crisis wards. Such places would be the Bedlam of the 21st century were it not for staff who go above and beyond the call of the ill-equipped prison system, administering decent and appropriate treatment to people who are victims of their country's almost vindictive indifference to social care. David Stubbs